The present invention relates generally to the field of camouflage. More particularly, the present invention is directed to a camouflaged structure and a method of camouflaging a structure against a background having a generally uniform composition.
Skylines are becoming less visually attractive due to the addition of tall structures that are not visually integrated into their surroundings and therefore stand out against their backgrounds, which frequently includes the sky. For example, with the continuing proliferation of mobile communications devices such as cellular telephones, personal digital assistants (PDAs), pagers, text messaging devices and the like, mobile communications service providers are constructing more and more antenna facilities, including cell towers, to improve the quality of existing services, increase the variety of services offered and increase the coverage area of their services. Thus, service providers are not only adding more cell towers to urban and suburban regions where cell towers already exist, they are constructing new towers in regions where no facilities had existed. In addition, a service region may have more than one service providers, each having its own cell towers separate from the cell tower(s) of the other service provider(s).
To optimize a cell tower""s coverage area, the cell tower should generally have its antenna(s) located high above the ground and at a location unobstructed by adjacent objects, such as buildings, trees and mountains, among others. To achieve this goal, cell towers typically extend above the highest features within their respective coverage area. Since cell towers generally extend above most or all of surrounding objects, viewers typically view these structures against a background sky.
Until relatively recently, service providers made no attempts to lessen the visual impact of their cell towers, other than perhaps painting them a with a light-color paint, such as a neutral gray. However, due to the large number of cell towers being constructed and increased concern over the aesthetic impact of these cell towers, more and more communities are banning cell towers within their jurisdictions. In response, service providers are attempting to make their cell towers more attractive, e.g., by disguising, or camouflaging, them as other objects, such as trees and cactuses. The realism of such disguises, however, has generally been less than desirable because the cell towers are typically significantly larger than typical simulated object and the geometrical requirements of the cell towers are not suited to simulating such objects.
Other conventional visual camouflaging techniques are generally not suitable for reducing the visual impact of cell site antennas and support towers. Conventional visual camouflaging techniques are generally one of two types. The first type is used when the environment surrounding an object to be visually concealed is non-uniform, i.e., contains a plurality of juxtaposed regions that visually contrast with one another to form repeating patterns, random patterns or a combination of repeating and random patterns. Such patterns are found in, e.g., cityscapes, landscapes and seascapes, which are generally viewed horizontally, and aerial views of natural and manmade features on the surface of the earth. In this type of camouflage, the goal is provide a pattern, or image, that simulates a pattern contained in the background against which a structure is viewed between a viewer and the structure so that the viewer confuses the simulated pattern with the background pattern and thus cannot readily distinguish the outline and/or other features of the structure from the background.
Examples of pattern camouflaging include U.S. Pat. No. 1,305,296 to MacKay and U.S. Pat. No. 2,292,848 to Robson. Each of these patents discloses a technique of painting a ship with various patterns comprising discrete regions of certain colors. In MacKay, the pattern is designed to simulate a seascape. In Robson, the pattern provides a compromise between concealment against a seascape and deceiving an observer as to attributes, such as size, shape, speed and direction of travel, of the ship once the ship has been spotted. Creating patterns from discrete regions of different colors is not suitable for concealing a structure against a generally uniform background such as the sky.
Examples of image camouflaging include U.S. Pat. No. 5,142,833 to Svehaug, U.S. Pat. No. 5,373,863 to Prizio and U.S. Pat. No. 5,220,631 to Grippin. Svehaug discloses a camouflage screen comprising a panel for placing between a user and an observer. The panel has a planar reflective surface that, when properly positioned, generally faces and is slanted toward the observer so that the user is concealed behind the panel and an image of the terrain below the slanted panel is reflected to the observer. Prizio discloses a camouflage blind for placing between one or more users and an observer. The blind comprises a plurality of panels pivotably attached to one another along adjacent edges so that the blind can be easily stored, transported and set up in the field. Each of the panels includes a planar reflective surface that, when properly positioned, generally faces the observer and reflects to the observer an image of one or more objects contained in the foreground of the reflective surface. The devices of Svehaug and Prizio are not suitable for being mounted on a structure, such as a cell tower.
Grippin discloses a camouflage device that uses optic fiber cables to conceal an object by transferring an image of the background (as viewed by a viewer) of the object to the foreground of the object. The device comprises a plurality of background imaging lenses, a plurality of foreground imaging lenses and a plurality of optic fibers that each connect a background imaging lens to a corresponding foreground imaging lens. The background imaging lens creates an image of the background that is transferred to the foreground imaging lens via the corresponding optic fiber. The foreground lens then forms an image of the background that is viewed by the viewer in the foreground of the device. Due to the necessity for optical quality lenses and the complexity of this device, it is not a practical option for camouflaging a large structure, such as a cell site antenna support tower. In addition, this device would be difficult, if not impossible, to adapt to provide such images for a full 360xc2x0 around a structure.
The second type of camouflaging technique is used to conceal an object against a background having a generally uniform composition of hue, saturation and brightness, wherein the object subtends a small arc of view. An example of this technique is U.S. Pat. No. 4,611,524 to Ferris, which discloses a camouflaged vehicle, such as an aircraft, surface vehicle or the like, at least a portion of which remains undetected until the vehicle subtends an arc of substantially five minutes when used against at least one predetermined light background reflectivity. One surface of the vehicle includes a substantial area of a predetermined reflectance that matches the reflectance of the predetermined light background. The area includes at least three defined portions, at least two of the portions having different reflectance so that when the reflectance of one of the defined portions is added to the total reflectance of the others of the three defined portions and the results averaged, they will have a reflectance substantially that of the predetermined light background. A limitation of this technique is that it is only suitable for objects subtending small arcs of view. Thus, this technique is not effective for large objects, such as cell site support towers, that are frequently viewed at a subtended arc of much greater than five minutes. In addition, this technique is not suitable when the foreground is brighter than the background.
In view of the foregoing, there is a need for a camouflaging technique that is economical and is capable of providing a large structure, such as a cell tower, with reduced visibility against a background, such as the sky, having a generally uniform composition of hue, saturation and brightness.
In a first aspect, the present invention is directed to a method of camouflaging a surface of a structure against a background containing a first color and a second color simultaneously or at different times. The method includes coloring a first region of the surface with a third color that is substantially the same as the first color and coloring a second region of the surface adjacent said first region with a fourth color that is substantially the same as the second color. A third region is provided between the first region and the second region so that the third region contains the third color and the fourth color combined to form a color gradient such that there is a gradual transition from the third color in the first region to the fourth color in the second region.
In a second aspect, the present invention is directed to a method of camouflaging an exterior surface of a structure not intended for human occupancy, wherein the camouflaged structure is located between a vantage point and a background and a foreground extends away from the structure in a direction opposite the background. The method includes the steps of providing the exterior surface of the structure not intended for human occupancy with at least one reflector having a reflective surface and positioning the at least one reflector such that the reflective surface reflects light from a portion of the foreground to the vantage point.
In a third aspect, the present invention is directed to a method of camouflaging an exterior surface of a structure located between a vantage point and a generally uniform background, wherein a foreground extends away from the structure in a direction opposite the background. The method includes the steps of providing the exterior surface with at least one reflector having a reflective surface, filtering from light incident the at least one reflector at least one wavelength of visible light and positioning the at least one reflector such that the reflective surface reflects at least a portion of the filtered light to the vantage point.
In a fourth aspect, the present invention is directed to a method of camouflaging an exterior surface of a structure located between a vantage point and a generally uniform background, wherein a foreground extends away from the structure in a direction opposite the background. The method includes the steps of providing the exterior surface with at least one semi-diffuse reflector having a reflective surface and positioning the at least one semi-diffuse reflector such that the reflective surface reflects light from a portion of the foreground to the vantage point.
In a fifth aspect, the present invention is directed to a method of camouflaging an exterior surface of a structure located between a vantage point and a generally uniform background, wherein a foreground extends away from the structure in a direction opposite the background. The method includes the steps of capturing at a first region light from at least one of the generally uniform background and the foreground, conducting the light to a second region located proximal to the exterior surface and spaced from the first region and emitting the light at the second region such that at least a portion of the light is directed toward the vantage point without forming an image.
In a sixth aspect, the present invention is directed to a camouflaged structure located between a background and a vantage point, wherein the background contains a first color and a second color simultaneously or at different times. The camouflaged structure includes a member having a surface visible from the vantage point and further includes a pattern of colors applied to said surface. The pattern comprises a first region, a second region and a third region. The first region contains a third color that is substantially the same as the first color. The second region contains a fourth color that is substantially the same as the second color. The third region contains the third color and the fourth color combined to form a color gradient such that there is a gradual transition from the third color in the first region to the fourth color in the second region.
In a seventh aspect, the present invention is directed to a camouflaged structure not intended for human occupancy, wherein the camouflaged structure is located between a generally uniform background and a foreground containing visible light and a vantage point. The camouflaged structure includes a member having an exterior surface and a reflector having a reflective surface. The reflector is attached to the structure and located adjacent the exterior surface between the exterior surface and the vantage point and the reflective surface is positioned so that at least a portion of the visible light contained in the foreground is reflected to the vantage point.
In an eighth aspect, the present invention is directed to a camouflaged structure located between a generally uniform background and a foreground containing visible light and a vantage point. The camouflaged member includes a member having an exterior surface and a semi-diffuse reflector having a reflective surface comprising a plurality of light diffusing elements. The semi-diffuse reflector is attached to the structure and located adjacent the exterior surface and between the exterior surface and the vantage point, and the reflective surface is positioned so that at least a portion of the visible light contained in the foreground is reflected to the vantage point.
In a ninth aspect, the present invention is directed to a camouflaged structure located between a generally uniform background and a foreground, wherein the foreground contains visible light and a vantage point and has a generally uniform composition comprising characteristic wavelengths of visible light. The camouflaged structure includes a member having an exterior surface and a reflector having a reflective surface. The reflector is attached to the structure and is located adjacent the exterior surface and between the exterior surface and the vantage point. The reflective surface is positioned so that at least a portion of the visible light contained in the foreground is reflected to the vantage point. A filter is located between the vantage point and the reflective surface. The filter is for filtering at least one wavelength of visible light that is different from the characteristic wavelengths of visible light.
In a tenth aspect, the present invention is directed to a camouflaged structure located between a generally uniform background and a foreground containing visible light and a vantage point. The camouflaged structure comprises a member that includes an exterior surface having a camouflaged region. A camouflaging member is attached to the camouflaged structure. The camouflaging member comprises a light capturing feature, a light emitting feature and a light conductor. The light capturing feature is spaced from the camouflaged region and is provided for capturing light from at least one of the generally uniform background and the foreground. The light emitting feature is located proximal to the camouflaged region and is provided for emitting light captured by the light capturing feature toward the vantage point without forming an image. The light conductor extends between the light capturing feature and the light emitting feature and is provided for conducting light captured by the light capturing feature to the light emitting feature.